Renault Laguna 1.9 use Elf oil. Elf is motor oil made just for Renault cars. In Renault services all use Elf oil. And people who drive Renault says that Elf is the best oil for Renault too.
It's capable of using any of the standard oil. Whether it's 100 150 300 or more. The thicker the better in a Renault Laguna since the engine does quite a bit of work in that model.
It can use Laguna 1 and moderate climate recommendations of 10W/40. It can run on almost any kind of oil once it reaches optimal temperatures but sometimes problems arise. Some even use filtered used cooking oil.